Generally, houses provide an environment appropriate for human life, to serve as dwelling units for human beings. For this, the houses are provided with cooling/heating systems.
A representative form of a dwelling in modem society is an apartment complex having a multi-floor structure in which a plurality of dwelling units are stacked in a vertical direction. Since the apartment complex has the particularity in that neighboring dwelling units jointly own floors and walls dividing them, the apartment complex has a necessity for a sound-insulating system capable of preventing transmission of noise between the dwelling sites, in addition to having cooling/heating systems.
A floor heating system should be designed to achieve a rapid room heating with low fuel costs and to have a high heat accumulation capacity for maintaining a heated state for a long time without addition of fuel.
The floor heating system is generally constructed by a wet construction method in which heat radiators are directly buried in concrete slabs by use of a mortar and a dry construction method in which a heat insulating material is disposed on concrete slabs and in turn, heat radiators are mounted to the heat insulating material.
Floor systems having the above heating system may take the form of a conventional floor system in which the heating system is directly constructed in concrete slabs, or a floating floor system in which the heating system is spaced apart upward from concrete slabs. The floating floor system is also called a double floor structure.
Giving a definition of a floor impact sound in association with the apartment complex, it is a noise being transmitted through floors between dwelling units. The floor impact sound has to be reduced as much as possible, and it has been found that the floating floor system is more advantageous to reduce the floor impact sound than the conventional floor system.
Conventionally, a floor sound-insulating system for reducing the transmission of an impact sound from upstairs to downstairs of the apartment complex has been separately constructed from a dry heating system for heating a floor. However, this has problems of disadvantageously increasing the thickness of the entire floor heating system and reducing floor-to-floor spans.
Further, since the dry floor heating system has to be constructed after completing construction of the floor sound-insulating system, there are problems of an excessive increase in construction costs and time. Furthermore, the increased thickness of the entire floor heating system increases the weight of the system, resulting in deterioration in safety of the entire building.
Japanese Patent Laid-open Publication No. 1997-0144289 discloses a double floor using a panel, which is formed at an upper surface thereof with lattice-shaped grooves and at side surfaces thereof with incisions. The disclosed invention proposes a cable extraction method for extracting cables from a lower space through the incisions to install the cables in the grooves. As will be appreciated, the double floor of the disclosed invention has no relation with the present invention dealing with floor sound insulation and heat insulation.
Japanese Patent Laid-open Publication No. 1993-0239904 discloses a double floor in which electric heating wires are installed in grooves formed at an upper surface of a panel. It will be also appreciated that the disclosed invention also has no relation with the present invention dealing with floor sound-insulation and heat-insulation.